Posts filed under General (2814)

April 4, 2025

Bike data

Tim Welch has produced a nice Auckland Cycleways Dashboard (it’s a draft at the moment, or ‘beta’ as we nerds say).

Here are some of the University-relevant routes (click to embiggen, as usual)

These are based on the Auckland Transport cycle counters, which are good for the city centre and major bike paths, but less informative for, say, people commuting in from the south, where there aren’t bike lanes or bike counters.

April 3, 2025

Tariff co-incidence

The tariffs announced by President Trump are based on what he describes as tariffs imposed by other countries on the US. These don’t bear any obvious relationship to the numbers that ordinary economists would describe as tariffs

However, a poster on Twitter, @nonagonono, found there is a strong relationship between the claimed tariff and the countries import/export balance with the US

We want to be a little sceptical of relationships that come just from data-dredging, with no real theory, but this relationship is tight enough that it probably isn’t just a coincidence, and probably does tell us something about the definition of ‘tariff’ the President is using.  If so, the ‘tariff’ of 20% that New Zealand allegedly imposes is actually a trade deficit of 20%, which is not quite what I get from NZ trade figures (24%) but is close enough that some slight changes in definition might explain it.

Food bank demand and supply

One News had a story based on a press release from NZ Food Network.  NZFN are a very worthwhile organisation. They coordinate donations and purchasing of bulk food for food banks, which they same amounts to about 45% of  the food being distributed.   If you were looking to donate to an organisation that helps feed people in this country, they look like a cost-effective choice. NZFN also run a food bank survey and a food security snapshot to find out about national needs and supply by food banks.

The headline figure in the press release is that the food banks “provided food to over 500,000 individuals each month”, based on the current survey. That’s a lot.

One News, but not the press release, said this was an all-time high.  Looking at previous annual reports and information sheets from NZFN, it doesn’t seem to be.  NZFN reported 454,000 in the first half of 2024, but their 2024 Annual Report said 655,152 for the second half of 2023 and the 2023 annual report says 480,104.  The number has been close to 10% of the New Zealand population ever since NZFN really got going. The scandal isn’t that the number is up, it’s that the number has been high for years!

What has changed noticeably is the total amount of food NZFN has been able to distribute.  The 2022 annual reports says about 8.6 million kg, the 2024 annual report says 5.6 million, and the 2024/2025 summer newsletter says 6.3 million.  They lost some government funding to purchase food, even as demand was increasing.  (If you look at the current press release you see a higher number that that for total food distributed, but I think that’s total distributed by the food hubs, rather than by NZFN)

I said “the number” is close to 10% of the population.  It’s a bit hard to find out exactly what this number means: is it genuinely unique people fed per month? Do the food hubs actually count how many people each recipient is feeding, and track individual visitors?  The reason I’m a bit suspicious about the number is a 2023 press release

Over half a million people are now being supported by NZFN food hubs each month but there is still a growing need. That works out to 1,868,491 more people being supported by NZFN, than they were in January 2020.

It’s not possible to get a total number of extra people from a monthly number, because you’d need to track individual people over the whole year; you can only get total number of visits.  Given this, it looks possible that that the 500,000 per month might also be total number of visits rather than unique monthly visitors.  It would still be a lot, either way.

You might think that I should answer this question by contacting NZFN rather than guessing.  I’m not sure I (as a One News reader) should have to, but I did actually try that.

April 1, 2025

United Rugby Championship Predictions for Week 15

Team Ratings for Week 15

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Leinster 13.06 12.09 1.00
Glasgow 9.54 9.39 0.10
Bulls 8.88 8.83 0.10
Munster 5.32 9.28 -4.00
Stormers 4.77 6.75 -2.00
Edinburgh 2.13 0.09 2.00
Lions 1.40 6.73 -5.30
Sharks 1.11 -2.94 4.10
Cheetahs 0.80 0.80 0.00
Ulster -0.58 2.52 -3.10
Connacht -1.42 -0.76 -0.70
Ospreys -1.72 -2.51 0.80
Scarlets -3.25 -10.65 7.40
Benetton -3.99 1.02 -5.00
Cardiff Rugby -4.21 -2.55 -1.70
Southern Kings -6.52 -6.52 0.00
Zebre -9.74 -16.17 6.40
Dragons -15.60 -15.41 -0.20

 

Performance So Far

So far there have been 112 matches played, 81 of which were correctly predicted, a success rate of 72.3%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Edinburgh vs. Dragons Mar 29 38 – 5 21.50 TRUE
2 Ulster vs. Stormers Mar 29 38 – 34 -0.90 FALSE
3 Connacht vs. Munster Mar 30 24 – 30 -3.70 TRUE
4 Bulls vs. Zebre Mar 30 63 – 24 21.60 TRUE
5 Scarlets vs. Ospreys Mar 30 38 – 22 -1.50 FALSE
6 Sharks vs. Leinster Mar 30 7 – 10 -7.40 TRUE
7 Benetton vs. Cardiff Rugby Mar 30 20 – 19 7.00 TRUE
8 Glasgow vs. Lions Mar 30 42 – 0 9.40 TRUE

 

Predictions for Week 15

Here are the predictions for Week 15. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Edinburgh vs. Sharks Apr 19 Edinburgh 6.50
2 Lions vs. Benetton Apr 19 Lions 10.90
3 Ospreys vs. Cardiff Rugby Apr 20 Ospreys 5.00
4 Stormers vs. Connacht Apr 20 Stormers 11.70
5 Munster vs. Bulls Apr 20 Munster 1.90
6 Dragons vs. Scarlets Apr 20 Scarlets -9.80
7 Leinster vs. Ulster Apr 20 Leinster 16.10
8 Zebre vs. Glasgow Apr 20 Glasgow -13.80

 

Top 14 Predictions for Round 21

Team Ratings for Round 21

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Stade Toulousain 12.71 8.76 3.90
Toulon 6.83 5.32 1.50
Bordeaux Begles 5.89 3.96 1.90
Montpellier 1.35 -0.96 2.30
Clermont 0.68 0.41 0.30
Stade Rochelais 0.67 4.85 -4.20
Castres Olympique 0.66 -0.09 0.80
Lyon 0.46 -0.18 0.60
Bayonne 0.37 -1.69 2.10
Racing 92 0.12 2.75 -2.60
Section Paloise -0.58 1.38 -2.00
Stade Francais -1.50 1.86 -3.40
USA Perpignan -3.92 -0.66 -3.30
Vannes -8.03 -10.00 2.00

 

Performance So Far

So far there have been 140 matches played, 105 of which were correctly predicted, a success rate of 75%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Bayonne vs. Lyon Mar 30 28 – 14 5.30 TRUE
2 Castres Olympique vs. Toulon Mar 30 28 – 26 -0.10 FALSE
3 Clermont vs. Stade Rochelais Mar 30 33 – 19 5.20 TRUE
4 Montpellier vs. Stade Francais Mar 30 38 – 32 9.00 TRUE
5 Stade Toulousain vs. Section Paloise Mar 30 55 – 10 16.30 TRUE
6 Vannes vs. USA Perpignan Mar 30 20 – 20 2.70 FALSE
7 Racing 92 vs. Bordeaux Begles Mar 31 36 – 31 0.30 TRUE

 

Predictions for Round 21

Here are the predictions for Round 21. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Castres Olympique vs. Vannes Apr 20 Castres Olympique 14.30
2 Lyon vs. Montpellier Apr 20 Lyon 7.00
3 Section Paloise vs. Bordeaux Begles Apr 20 Section Paloise 0.50
4 Stade Francais vs. Stade Toulousain Apr 20 Stade Toulousain -7.10
5 Stade Rochelais vs. Bayonne Apr 20 Stade Rochelais 6.10
6 Toulon vs. Clermont Apr 20 Toulon 13.20
7 USA Perpignan vs. Racing 92 Apr 20 USA Perpignan 2.30

 

Super Rugby Predictions for Week 8

Team Ratings for Week 8

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Blues 12.15 14.92 -2.80
Chiefs 11.94 11.43 0.50
Hurricanes 9.26 10.97 -1.70
Crusaders 9.13 8.99 0.10
Brumbies 4.70 6.19 -1.50
Reds 1.67 1.35 0.30
Highlanders -1.80 -2.50 0.70
Western Force -5.40 -6.41 1.00
Waratahs -5.43 -5.17 -0.30
Fijian Drua -7.36 -7.98 0.60
Moana Pasifika -8.34 -11.25 2.90

 

Performance So Far

So far there have been 34 matches played, 24 of which were correctly predicted, a success rate of 70.6%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Hurricanes vs. Waratahs Mar 28 57 – 12 16.70 TRUE
2 Brumbies vs. Highlanders Mar 28 34 – 27 11.10 TRUE
3 Crusaders vs. Moana Pasifika Mar 29 29 – 45 23.60 FALSE
4 Reds vs. Western Force Mar 29 28 – 24 11.30 TRUE

 

Predictions for Week 8

Here are the predictions for Week 8. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Chiefs vs. Reds Apr 04 Chiefs 14.30
2 Moana Pasifika vs. Waratahs Apr 05 Moana Pasifika 1.10
3 Fijian Drua vs. Crusaders Apr 05 Crusaders -12.50
4 Blues vs. Hurricanes Apr 05 Blues 6.40
5 Western Force vs. Highlanders Apr 05 Western Force 0.40

 

Rugby Premiership Predictions for Round 14

Team Ratings for Round 14

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Bath 13.73 5.55 8.20
Sale Sharks 4.22 4.73 -0.50
Leicester Tigers 4.03 3.27 0.80
Gloucester 3.42 -9.04 12.50
Bristol 3.07 9.58 -6.50
Northampton Saints 2.23 7.50 -5.30
Harlequins 1.63 -2.73 4.40
Saracens 1.51 9.68 -8.20
Exeter Chiefs -4.48 1.23 -5.70
Newcastle Falcons -18.58 -19.02 0.40

 

Performance So Far

So far there have been 65 matches played, 43 of which were correctly predicted, a success rate of 66.2%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Sale Sharks vs. Northampton Saints Mar 29 27 – 24 9.90 TRUE
2 Bath vs. Harlequins Mar 30 47 – 28 18.50 TRUE
3 Exeter Chiefs vs. Newcastle Falcons Mar 30 17 – 15 25.30 TRUE
4 Gloucester vs. Bristol Mar 30 53 – 28 2.30 TRUE
5 Leicester Tigers vs. Saracens Mar 31 22 – 29 13.00 FALSE

 

Predictions for Round 14

Here are the predictions for Round 14. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Newcastle Falcons vs. Northampton Saints Apr 19 Northampton Saints -14.30
2 Exeter Chiefs vs. Bath Apr 20 Bath -11.70
3 Harlequins vs. Sale Sharks Apr 20 Harlequins 3.90
4 Saracens vs. Gloucester Apr 20 Saracens 4.60
5 Bristol vs. Leicester Tigers Apr 21 Bristol 5.50

 

NRL Predictions for Round 5

Team Ratings for Round 5

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Storm 9.51 9.29 0.20
Panthers 7.20 8.50 -1.30
Sharks 5.16 5.10 0.10
Roosters 4.38 7.44 -3.10
Sea Eagles 4.11 2.97 1.10
Bulldogs 2.04 0.07 2.00
Cowboys 1.63 4.11 -2.50
Broncos 0.23 -1.82 2.00
Knights -0.88 -0.05 -0.80
Warriors -1.24 -1.68 0.40
Raiders -3.19 -3.61 0.40
Rabbitohs -3.28 -4.35 1.10
Titans -3.63 -5.50 1.90
Dolphins -3.75 -1.96 -1.80
Dragons -4.34 -4.55 0.20
Eels -5.77 -3.02 -2.80
Wests Tigers -8.17 -10.97 2.80

 

Performance So Far

So far there have been 32 matches played, 18 of which were correctly predicted, a success rate of 56.2%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Rabbitohs vs. Panthers Mar 27 28 – 18 -9.20 FALSE
2 Roosters vs. Titans Mar 28 12 – 30 13.50 FALSE
3 Dolphins vs. Broncos Mar 28 12 – 20 -3.40 TRUE
4 Dragons vs. Storm Mar 29 14 – 8 -12.50 FALSE
5 Cowboys vs. Raiders Mar 29 30 – 20 7.40 TRUE
6 Sharks vs. Bulldogs Mar 29 6 – 20 8.00 FALSE
7 Sea Eagles vs. Eels Mar 30 26 – 12 12.70 TRUE
8 Wests Tigers vs. Warriors Mar 30 24 – 26 -3.70 TRUE

 

Predictions for Round 5

Here are the predictions for Round 5. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Raiders vs. Sharks Apr 03 Sharks -5.30
2 Panthers vs. Cowboys Apr 04 Panthers 8.60
3 Rabbitohs vs. Roosters Apr 04 Roosters -4.70
4 Eels vs. Dragons Apr 05 Eels 1.60
5 Titans vs. Dolphins Apr 05 Titans 3.10
6 Broncos vs. Wests Tigers Apr 05 Broncos 11.40
7 Sea Eagles vs. Storm Apr 06 Storm -2.40
8 Bulldogs vs. Knights Apr 06 Bulldogs 5.90

 

AFL Predictions for Week 5

Team Ratings for Week 5

The basic method is described on my Department home page.
Here are the team ratings prior to this week’s games, along with the ratings at the start of the season.

Current Rating Rating at Season Start Difference
Hawthorn Hawks 24.22 21.95 2.30
Brisbane Lions 19.46 22.65 -3.20
Geelong Cats 17.06 15.04 2.00
Western Bulldogs 13.83 18.20 -4.40
Collingwood 12.95 5.39 7.60
GWS Giants 9.70 9.08 0.60
Adelaide Crows 8.68 2.69 6.00
Sydney Swans 8.31 12.60 -4.30
Port Adelaide Power 3.39 7.63 -4.20
Carlton Blues 2.73 5.01 -2.30
St Kilda Saints 2.41 0.89 1.50
Gold Coast Suns 2.15 -6.41 8.60
Fremantle Dockers 1.29 5.99 -4.70
Melbourne Demons -10.70 -0.21 -10.50
Essendon Bombers -11.08 -10.15 -0.90
North Melbourne -27.64 -37.08 9.40
Richmond Tigers -33.44 -31.00 -2.40
West Coast Eagles -35.71 -34.67 -1.00

 

Performance So Far

So far there have been 27 matches played, 17 of which were correctly predicted, a success rate of 63%.
Here are the predictions for last week’s games.

Game Date Score Prediction Correct
1 Essendon Bombers vs. Port Adelaide Power Mar 27 72 – 60 -6.30 FALSE
2 Carlton Blues vs. Western Bulldogs Mar 28 75 – 83 -12.10 TRUE
3 Brisbane Lions vs. Geelong Cats Mar 29 70 – 61 5.60 TRUE
4 Melbourne Demons vs. Gold Coast Suns Mar 29 62 – 120 6.40 FALSE
5 St Kilda Saints vs. Richmond Tigers Mar 29 135 – 53 28.80 TRUE
6 Hawthorn Hawks vs. GWS Giants Mar 29 76 – 64 28.10 TRUE
7 Adelaide Crows vs. North Melbourne Mar 30 114 – 78 49.50 TRUE
8 West Coast Eagles vs. Fremantle Dockers Mar 30 68 – 106 -36.70 TRUE

 

Predictions for Week 5

Here are the predictions for Week 5. The prediction is my estimated expected points difference with a positive margin being a win to the home team, and a negative margin a win to the away team.

Game Date Winner Prediction
1 Collingwood vs. Carlton Blues Apr 03 Collingwood 10.20
2 Geelong Cats vs. Melbourne Demons Apr 04 Geelong Cats 38.80
3 Gold Coast Suns vs. Adelaide Crows Apr 05 Gold Coast Suns 4.50
4 Richmond Tigers vs. Brisbane Lions Apr 05 Brisbane Lions -41.90
5 North Melbourne vs. Sydney Swans Apr 05 Sydney Swans -25.00
6 GWS Giants vs. West Coast Eagles Apr 06 GWS Giants 56.40
7 Port Adelaide Power vs. St Kilda Saints Apr 06 Port Adelaide Power 12.00
8 Fremantle Dockers vs. Western Bulldogs Apr 06 Western Bulldogs -1.50

 

March 31, 2025

Bogus polls are bogus even for the good guys

Nature magazine (yes, that one) has a headline 75% of US scientists who answered Nature poll consider leaving.

This is a more honest phrasing that one usually gets in bogus poll headlines, but it’s still bogus.  The ‘poll’ was

Responses were solicited earlier this month on the journal’s website, on social media and in the Nature Briefing e-mail newsletter. Roughly 1,650 people completed the survey.

The other problem with the poll is that ’emigrational ideation’, as one might call it, is a very low bar. Lots of people consider doing things. Many fewer actually do them. People having been claiming they are considering leaving the US for a long time, and we don’t know from the ‘poll’ how the current numbers compare to the usual state of affairs. Remember this cartoon, from 2006:

In fact, I think it’s quite likely that there are more scientists than before actively looking into leaving the US.  Anecdotally, we are getting more enquiries here and more US applicants to advertised positions.  You might think this sort of anecdata is a pretty weak basis for conclusions . You’d be right, but it’s still better than a bogus poll.